Something's been bugging me...

August 31, 2009 4:25 AM

WeirdBugFilter: What is this bug? Entymologists please help!

These things have periodically wandered through my ground-floor bathroom and main room. The first time I saw one I thought it was one of those little plastic toy insects, and then it started moving which was slightly disturbing. The closest candidate I can come up with is the stink beetle but this species is native to the deserts of northern Mexico, whereas I am in chilly, damp northern England. Furthermore, it has never displayed any behaviour like that of the stink beetle despite my ignorant prods and pokes.

More images of this curious creepy crawly might help you identify it from its feelers or thorax or abdomen shape.

posted by fearnothing to science & nature (10 comments total)

I'm no entomologist, but it looks like a Cellar or Churchyard Beetle to me.
posted by miratime at 4:40 AM on August 31

I don't know its name, I know only that I grew up with these guys (Bremen, Germany), and even here in Sweden I occasionally see them. It's probably something like the North European Generic Summer Beetle (but I'd like to know, too). They live under stones and in basements (we even had them occasionally in the attic and bedrooms), they do their little beetle things there and scuttle away when they notice that they've been noticed. They don't stink, but they are clumsy enough to get in the way and get crunched upon which is no fun, especially when you're barefoot.
posted by Namlit at 4:46 AM on August 31

It reminds me of the violet beetle. When you lift it into the light, does it have iridescent rims to it's back end?
posted by Solomon at 5:23 AM on August 31

miratime's link looks highly likely, with the exception that none of the ones I've encountered have used any kind of defensive response. The shell is not quite matte black, it does have a little shine to it, but no iridescence.
posted by fearnothing at 5:40 AM on August 31

For what it's worth, when I grew up in Sweden we would call those "Svartbaggar". Perhaps it's Blaps lethifera?
posted by gemmy at 6:13 AM on August 31

It is either a darkling beetle or a false darkling beetle. To determine the difference I would need to see it.
posted by bolognius maximus at 8:21 AM on August 31

so far as I can tell, "darkling beetle" refers to the entire family Tenebrionidae, of which the churchyard beetle is one. Perhaps it would help if I said that the beetle appears physically identical to this diagram, even to the point of having the same number of barbs on its legs. The only reason I'm not 100% certain is because it never exhibited the defence behaviour described on the page miratime linked.
posted by fearnothing at 9:11 AM on August 31

Helpful hint: apart from a clear image, the most important data you can supply is size. Whenever possible - as it is clearly possible in this case - give a sense of scale by dropping a quarter or some other easily understood object next to the bug.
posted by VikingSword at 9:26 AM on August 31

Yes, it's definitely a Tenebrionid. More than that needs a closer look than a camera will give. It might well be the beetle miratime linked to even if it doesn't do an amusing headstand. Tenebrionids are spectacularly stupid, and it may not have noticed you poking it.

You could try asking these people if you need to be more specific.
posted by Acari at 9:53 AM on August 31

ah, size was 25mm not including antennae
posted by fearnothing at 9:54 AM on August 31